1. Mathematics of Real-World Systems Doctoral Training Centre, University of Warwick , Coventry, CV35 9EF, UK
2. School of Life Sciences, University of Warwick , Coventry, CV35 9EF, UK
3. School of Mathematics & Statistics, University of Sheffield , Sheffield, S3 7RH, UK
4. Bateson Centre, University of Sheffield , Sheffield, S10 2TN, UK